Sea urchins are spiny marine organisms; many different species are found in oceans around the world. Male and female individuals produce eggs and sperm that are shed freely into seawater. Scientists have long used the urchin as a model for studying fertilization and development.

These sea urchin (Lytechinus pictus) embryos were fertilized at the same time as those in the movie Sea urchin embryos treated with vinblastine. They develop normally, as they were not treated with the chemotherapy drug vinblastine.

Elapsed time 5 hours.

A population of sea urchin eggs was fertilized. Half the population was treated with vinblastine and mounted in seawater between a slide and coverslip (using a silicon spacer). Please see the movie Sea urchin embryos treated with vinblastine for the drug-treated embryos. The untreated embryos served as a control. Images of both treated and untreated embryos were taken at room temperature on a compound inverted microscope using a 20x DIC objective and digital camera.